问题描述：
帮我吧英语句子单数的转换成复数,复数转换成单数!
1.This is a bus
2.That is a box
3.It is an orange
4.These are English books
5.Those are Chinese books
6.They are my pencils
1.This is a bus
2.That is a box
3.It is an orange
4.These are English books
5.Those are Chinese books
6.They are my pencils
问题解答：
我来补答展开全文阅读